Device and method for establishing an artificial arterio-venous fistula

ABSTRACT

A shunt rivet for implantation in the aorta and inferior vena cava to treat chronic obstructive pulmonary disease, and a method of treating chronic obstructive pulmonary disease.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. application. Ser. No.10/927,704 filed Aug. 27, 2004, which is incorporated herein byreference in its entirety.

FIELD OF THE INVENTION

The inventions described below relate to treatments for pulmonaryhypertension and vascular surgery.

BACKGROUND OF THE INVENTION

Chronic obstructive pulmonary disease (COPD), chronic hypoxia,hypertension, and left ventricular hypertrophy and pulmonaryhypertension are diseases of the cardiopulmonary system. Chronicobstructive pulmonary disease (COPD), which includes chronic bronchitisand emphysema, is a slowly progressive lung disease caused primarily bysmoking. In COPD, the lungs are damaged and the airways are partlyobstructed, making it difficult to breath and leading to a gradual lossof lung function. Symptoms of COPD include chronic cough, excessivesputum production, low blood oxygen levels and severe disablingshortness of breath. COPD represents the fourth leading cause of deathin the United States. Chronic hypoxia (reduction of oxygen supply to thebody despite adequate blood flow through the body), hypertension, andleft ventricular hypertrophy are related conditions which may besymptomatic of COPD or coincident with COPD.

These serious conditions affect many people, and the primary treatmentsare merely ameliorative. The primary treatments for COPD includeavoidance of irritants such as tobacco smoke and breathing supplementaloxygen. In advanced cases of COPD, lung reduction surgery is sometimesperformed, but it is not clear that it helps. There is no known cure forCOPD.

An aortocaval fistula (ACF) is a rare clinical condition that can beeither spontaneous (80% of the cases), related to abdominal aorticaneurysm, or the result of some trauma such as lumbar disk surgery. Itis currently seen as a defect that should be cured with surgery and,possibly, stent-graft implantation in the aorta.

Contrary to this understanding, an intentionally formed aortocavalfistula appears to be a viable treatment for COPD. Recently, in ourco-pending U.S. patent application Ser. No. 10/820,169 (U.S. Pub.2004/0249335 A1) filed Apr. 6, 2004, entitled Implantable ArteriovenousShunt Device and listing John L. Faul, Toshihiko Nishimura, Peter N. Kao& Ronald G. Pearl as inventors (the entirety of which is herebyincorporated by reference), we propose creation of an artificialaortocaval fistula as a treatment for COPD, and we disclose the methodof creating the fistula and an implantable shunt for maintaining theaortocaval fistula.

Shunts or stents for connecting blood vessels have been proposed for thetreatment of coronary artery disease. Makower, Device, System And MethodFor Interstitial Transvascular Intervention, U.S. Pat. No. 6,746,464(Jun. 8, 2004) (filed Oct. 28, 1998) discloses a stent with a shorttubular section spanning the thickness of a coronary artery and anadjacent parallel coronary vein. This stent includes “clovers” on eitherend of the stent, and these clovers fold radially outwardly to obstructmovement of the stent through the vessel walls. Two clovers on theproximal end of the stent are orthogonal (relative to the radial crosssection of the stent) to two clovers on the distal end of the stent, andthe interconnecting wires are parallel to the longitudinal axis of thedevice.

SUMMARY OF THE INVENTION

The devices and methods described below provide for treatment of COPD,hypertension, and left ventricular hypertrophy, and chronic hypoxia. Avascular shunt rivet is disclosed which serves to hold contiguous pointsof the patient's aorta and inferior vena cava (or other arteries andthere associated veins, such as the femoral artery and femoral vein, orthe carotid artery and the carotid vein) together and maintain an openflow path from the aorta to the vena cava. The device functions as arivet, holding the two vessel walls in close proximity, and as a shunt,permitting and maintaining flow from one blood vessel to the other. Thedevice is implanted, between the aorta and inferior vena cava, as atreatment for pulmonary hypertension, COPD and chronic hypoxia.

The shunt rivet is provided in the form of an expandable wire framestructure adapted for transcutaneous delivery and deposit at the desiredimplantation site. The wire frame structure may be compressed into asmall diameter configuration to fit within the distal tip of a deliverycatheter. Upon expulsion from the catheter, the wire frame structureresiliently or pseudoelastically expands into a flow-through rivetcomprising a tube with expanded heads at either end. When the rivet isreleased within an artificial fistula formed through the aorta and venacava walls, it expands to trap the walls between the two expanded heads.The tubular section between the two expanded head may resilientlyexpand, and may also be balloon-expanded or otherwise plasticallydeformed to enlarge the flow-through lumen of the tubular section.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates the method of installing the shunt rivet to createand maintain an artificial aortocaval fistula.

FIG. 2 illustrates an aortocaval shunt rivet in its restrainedcondition.

FIG. 3 illustrates the aortocaval shunt rivet of FIG. 2 in a resilientlyexpanded configuration.

FIG. 4 is a perspective view of the aortocaval shunt rivet of FIG. 2 ina resiliently expanded configuration.

FIG. 5 illustrates the aortocaval shunt rivet of FIG. 2 in a fullyexpanded configuration.

FIGS. 6 through 11 illustrate the deployment of the aortocaval shuntrivet of FIG. 2.

FIG. 12 illustrates an aortocaval shunt rivet with asymmetrically shapeddistal and proximal flanges.

FIG. 13 illustrates an aortocaval shunt rivet with asymmetrically shapeddistal and proximal flanges.

FIGS. 14, 15 and 16 illustrate an aortocaval shunt rivet with strutmembers that form diamond-shaped cells in the central section uponexpansion.

FIGS. 17 and 18 illustrates an aortocaval shunt rivet formed with asingle wired wrapped to form the device.

FIG. 19 shows a detail of the clinch member, illustrating radiopaquemarkers on the shunt rivet.

FIGS. 20 and 21 illustrates a mandrel useful for forming andtraining/heat setting the shunt rivets

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 illustrates the method of installing the shunt rivet to createand maintain an artificial aortocaval fistula. The patient 1 is shownwith a delivery catheter 2 inserted into the left femoralartery/external femoral artery 3L and pushed upwardly through the leftcommon iliac artery 4L to a point just above the aortic/iliacbifurcation in the distal abdominal aorta 5. The inferior vena cava 6runs parallel to the aorta, and typically is contiguous with the aorta.As shown in the illustration, the left femoral artery provides a nearlystraight pathway to a suitable site of the artificial aortocaval fistula7 within the abdominal aorta (the right femoral vein 9R also provides astraight pathway to the same site on the vena cava side, and may be alsobe used as an access pathway). The fistula is created by forming a smallhole or slit through the walls of both the aorta and the vena cava atimmediately adjacent sites, and is maintained by inserting the shuntrivet 8 described below. The device may also be implanted via a routethrough the left femoral vein 9L, or through the right femoral artery 3Rand/or right common iliac artery 4R, though these pathways are notexpected to be so readily navigable. The shunt rivet may also beinstalled in an artificial arterio-venous fistula formed between thefemoral vein and femoral artery on either side of the body, indicated asitems 10R and 10L, or between the iliac artery and the femoral vein, andat locations in the aorta above the renal arteries.

FIG. 2 illustrates the aortocaval shunt rivet 8 in its restrainedcondition, while FIG. 3 illustrates the aortocaval shunt rivet of FIG. 2in its resiliently expanded configuration. The shunt rivet may be formedfrom a single tube 11 of resilient material, such as nitinol, springsteel, glass or carbon composites or polymers, or pseudoelastic (at bodytemperature) material such as nitinol or comparable alloys and polymers,by laser cutting several closed-ended slots 12 along the length of thetube (leaving the extreme distal and proximal edges of the tube intact)and cutting open-ended slots 13 from the longitudinal center of the tubethrough the distal and proximal edges of the tube. The open-ended slotsare cut between each pair of closed-end slots to form a number of loops14 joined at the center section by waist segments 15. Though the shuntrivet illustrated in these figures can be made of several loops of wirewelded together at the waist section, and many other fabricationtechniques, manufacture from a single tube as illustrated has beenconvenient.

After the tube is cut as described above, it is formed into its eventualresiliently expanded configuration illustrated in FIG. 3. In thisconfiguration, the loops turn radially outwardly from the centersection, and evert toward the center plane of the center section, thusforming clinch members 16 in the form of arcuate, everted, petaloidframes at either end of the loop, extending from the generally tubularcenter section formed by the waist segments 15. For clarity, the termeverted is used here to mean that the arc over which the petaloid frameruns is such that the inside surface of the device as configured in FIG.2 faces radially outwardly from the cylinder established by the tube.FIG. 4 is a perspective view of the shunt rivet in the resilientlyexpanded configuration illustrated in FIG. 3, more clearly illustratingthe relationship between the several petaloid frames at each end of theshunt rivet.

FIG. 5 shows a side view of the aortocaval shunt rivet of FIG. 2 in afully expanded configuration. Even after the device has resilientlyexpanded to the extent possible given its impingement upon the walls ofthe aorta and the vena cava, the center section may be further expandedby plastic deformation. This may be accomplished by inflating a balloonwithin the center section, inflating the balloon, and expanding thecenter section beyond its elastic or superelastic deformation range. Byplastically deforming the center section of the shunt rivet, the centersection becomes more rigid and able to withstand the compressive forceof the walls of the aorta and vena cava.

As illustrated, the construction provides several pairs oflongitudinally opposed (that is, they bend to come into close proximityto each other, and perhaps but not necessarily, touch) and aligned (theyare disposed along the same longitudinal line) distal and proximalpetaloids. Overall, the petaloid frames of the distal section form a“corolla” (analogous to the corolla of a flower) flange or rivet clinch,which impinges on the vena cava wall and prevents expulsion into theaorta, and the petaloid frames of the proximal section form a corolla,flange or rivet clinch (this clinch would be analogous to a rivet head,but it is formed like the clinch after insertion of the rivet), whichimpinges on the aorta wall and prevents the expulsion of the shunt rivetinto the vena cava, and the central section 17 forms a short length ofrigid tubing to keep the fistula open. The resilient apposition of thetwo distal and proximal flanges or corollas so formed will securely holdthe shunt rivet in place by resiliently clamping the walls of the aortaand vena cava (even over a considerable range of wall thickness or “griprange”).

Referring to FIGS. 2 through 5, the shunt rivet may be manufactured withan overall initial length L of about 8 to 10 mm to obtain a grip range Gof about 3 mm (given a typical aortic wall thickness of 2 mm and atypical inferior vena cava wall thickness of 1 mm at the target site), aclinch allowance C of at least about 3 mm (the clinch allowance is thedistally protruding portion of a rivet that is turned over, curled orflattened to form the formed head), a formed or blind head allowance Aof about 10-16 mm (we use the term blind head to refer to the distalhead, which is the head that is formed on the blind side of the joint),a head diameter H of 5-16 mm, an initial shank diameter D1 of 3-8 mm (inthe resiliently expanded configuration, prior to plastic deformation), afinal shank diameter D2 of 5-12 mm to create a flow through lumen ofabout 5-10 mm diameter. The grip strength of the shunt rivet shouldprovide for a slight compressive force exerted by the opposing clinchmembers on the intervening blood vessel walls. Thus, the shunt rivet isformed such that, in the resiliently expanded configuration, produces agrip strength in the range of 0.1 to 1.5 oz (about 3 to 45 gram-force)per clinch member upon the intervening blood vessels of the expectedthickness.

FIGS. 6 through 11 illustrate the method of releasing the shunt rivet sothat the distal clinch members are released within the vena cava and theproximal clinch members are released within the aorta. Prior toinsertion of the delivery catheter, the surgeon performing theimplantation will image the aorta and inferior vena cava withappropriate fluoroscopic, ultrasonic, or other imaging methods, andcreate a pilot hole in the vessel walls with a crossing catheter. Asshown in FIG. 6, the shunt rivet is housed within the distal tip of adelivery catheter 23, and is entirely restrained within the deliverycatheter. The delivery catheter includes an outer sheath 24, a shaft 25which is longitudinally slidable within the outer sheath, and a taperedor rounded tip 26 disposed on the shaft. The tapered may be mounted on aseparate shaft, slidably disposed within the shaft 25, so that it may bepushed through the prepared aperture while holding the remainder of thedevice steady within the aorta. The distal edge of the outer sheath mayalso be rounded or tapered, as shown. A distally facing shoulder 27 onthe shaft, just proximal to the shunt rivet, serves to keep the shuntrivet in place longitudinally as the outer sheath is withdrawn. A guidewire lumen 28 may be provided in the shaft for use with a guide wire 29,and may extend to the proximal end of the shaft for over-the-wireoperation or may exit the shaft just proximal to the shunt rivet holdingsegment for monorail guidewire operation, and other guide wireconfigurations may also be used. A balloon 30 may be disposed on theshaft (and a suitable balloon inflation lumen provided in the shaft, anda suitable inflation pressure source in fluid communication with thelumen).

As shown in FIG. 7, the distal tip of the delivery catheter is pushedthrough a small aperture in the walls of the aorta and vena cava (items31 and 32) (the aperture is made by the operator, using a separate orintegral punch, needle or lance) to create the artificial aortocavalfistula. After the distal tip has entered the vena cava, the outersheath is pulled proximally to release the distal petaloids, as shown inFIG. 8. After the distal petaloids have reverted to their unrestrainedconfiguration, the entire device is pulled proximally to seat the distalpetaloids against the inner wall of the vena cava. Prior to completerelease of the shunt rivet, the operator should confirm that itslocation is acceptable (any suitable imaging technique may be used). Toallow retraction in case the shunt rivet must be repositioned, a hook 33protrudes radially from the shaft 25 and passes through a loop of theshunt rivet. This traps and secures the shunt rivet within the outersheath 24 until the outer sheath is moved proximally to release theproximal clinch members, so that the operator may pull the shunt rivetback into the outer sheath in case its location, as visualized prior tocomplete release of the shunt rivet, is undesirable. Any other retainingmeans, such as a resilient or spring-loaded detent, a retractable pawlwhich engages a loop of the shunt rivet, of a retractable hook extendinginwardly from the outer sheath, may be used in place of the illustratedhook.

Then the outer sheath is pulled further proximally to release theproximal petaloids, as shown in FIG. 9. With the shunt rivet securelyset in the artificial fistula, the center section may then be expandedby inflating the balloon as shown in FIG. 10. Upon withdrawal of theshaft, the shunt rivet remains in place to hold the two perforations inthe blood vessel wall in apposition to each other to maintain thefistula, and to maintain an open shunt pathway between the aorta andvena cava, as shown in FIG. 11.

The final form of the shunt rivet is, according to the abovedescription, accomplished with the method that includes forming thegenerally tubular structure having a central section with a firstdiameter, a proximal clinch section defined by one or more clinchmembers, and a distal clinch section defined by one or more clinchmembers, training the proximal and distal clinch members to make themresiliently biased to bend radially outwardly from the central section;then resiliently compressing the tubular structure to maintain agenerally tubular shape and restraining the compressed tubular structurein a compressed configuration suitable for percutaneous insertion intothe body; inserting the structure through apposing apertures in theaorta wall and vena cava wall of a patient such that the distal clinchmembers protrude into the vena cava of the patient and the centralsection is disposed within the apertures; and then releasing the distalclinch members to permit resilient expansion of the distal clinchmembers followed by expanding the central section through plasticdeformation to larger diameter and releasing the proximal clinch membersto permit resilient expansion of the proximal clinch members (theproximal clinch members may be released before or after expansion of thecentral section).

The shunt rivet illustrated above may be modified as shown in FIGS. 12and 13, which show an aortocaval shunt rivet with asymmetrically shapeddistal and proximal flanges. In FIG. 12, the shunt rivet 35 is similarto the shunt rivet of FIGS. 2 through 4, and includes the centralsection, the distal flange comprised of multiple petaloid wire-framemembers 16 d, and the proximal flange comprised of multiple petaloidwire-frame members 16 d. In this embodiment, the distal corolla ishorn-shaped, “salverform” or “funnelform” (as those terms are used inbotany), with the petaloids arcing outwardly without everting (without asubstantial arc in the proximal direction), while the proximal corollais perianth-like, arcing outwardly and everting with a substantial arcin the distal direction. Each petaloid is significantly reflexed, likethe perianth of a narcissus cyclamineus. FIG. 13 illustrates anotherembodiment of the aortocaval shunt rivet with asymmetrically shapeddistal and proximal flanges. In FIG. 13, the proximal petaloids arehighly reflexed, and evert to form pigtails with an arc of over 180° ,and preferably, as illustrated, an arc in excess of about 270° , suchthat the proximal petaloids bend radially inwardly toward the tips 36 topresent a length of wire 37, rather than the tip of the petaloids, forimpingement on the blood vessel wall. One or both of the distal orproximal petaloids/clinch members may be modified to form the pigtailsillustrated in FIG. 13. In the embodiments shown, the petaloids aregamopetalous (with the petals united by their margins, at least at thebase, as in FIG. 2 et seq.), but they may also be polypetalous as shownbelow FIGS. 14, 15 and 16. The embodiments shows are also actinomorphic,though they may be constructed in zygomorphic fashion with asymmetricalpetaloids.

FIGS. 14, 15 and 16 illustrate an aortocaval shunt rivet 8 with diamondshaped strut members in the central section. This shunt rivet provides acentral section 17 with a series of expandable loops joined bycircumferentially oriented struts 38. FIG. 14 illustrates a tube 11 withnumerous slots cut into it to form the shunt rivet shown in FIG. 16.Slots 12 are closed-end slots, leaving a loop 14 extending from thecentral section 17 to form a clinch member cell 39. Slots 40 are open orclosed-end slots extending from the center of the device, leaving smallcircumferential struts 41 connecting adjacent cells of the device. Slots42 are open or closed-end slots extending from the center section of thedevice, leaving larger waist sections 43 connecting the circumferentialstruts with adjacent clinch member cells of the device. Slots 44 areclosed-end slots extending through the waist sections. As shown in FIG.15, some waste area (segments intended to be removed) 46 shown in FIG.14 are cut away and discarded, leaving expandable waist section cells 47and clinch cells 39, interconnected by the circumferential struts 38.Though the device is illustrated with three clinch members on each end,the number of clinch members formed in the shunt rivet may be varied.The waist section cells and clinch member cells, can, as shown at 48,share struts which define contiguous cells. As shown in FIG. 16 thewaist section cells, when expanded, form the diamond shaped cells of thecentral section. The clinch member cells comprise petaloid cells whichmay be described as lanceolate (narrow and tapering to an apex (thoughthe apex is preferably blunt)), or ovate (having a broad base and narrowtip) rather than reniform or orbicular. The tip of the petaloid ispreferably obtuse, rounded or blunt. As can be appreciated from FIG. 16the clinch members may also be described as longitudinally extendingwires which connect the longitudinally tips of adjacent waist sectioncells.

FIGS. 17 and 18 illustrate an aortocaval shunt rivet 51 formed with asingle wired wrapped to form the device. In this device, a single wirehas been wrapped around a specially formed mandrel to form a number ofclinch members 52 on one end of the device and a number of clinchmembers 53 on the other end of the device. As illustrated, each clinchmember is slanted relative to the radius of the device, and the wiresforming the waist segment of the device are also oblique to thelongitude of the device. As viewed from the top, each cinch membercomprises a substantially circular arc, and the wire continues from thearc longitudinally toward the opposite end of the device, formingstraight waist segment 54 where it runs substantially parallel to thelong axis of the device until it arcs circumferentially away from theprevious arc to form the clinch member on the opposite end, whereafterit loops around to extend retrograde relative to the circumference,forming waist segment 55 running obliquely relative to the long axis,and back toward the first end of the device until it curves againcircumferentially forward to form the loop of the next clinch membercircumferentially adjacent the first loop and longitudinally in linewith the immediate previously formed clinch member on the opposite endof the shunt rivet, and continues in this fashion until the entiretubular structure of the device is achieved. In tracing its path, thewire may cross over one or more other portions of the wire.

FIG. 19 shows a detail of the clinch member, illustrating radiopaquemarkers on the shunt rivet. A radiopaque marker may be provided in theform of a radiopaque rivet 61 disposed near the tip of the clinch member16, or it may be provided in the form of a wrapped coil of radiopaquewire or thread 62. The radiopaque markers may be comprised of platinum,iridium, tantalum, barium sulfate or other radiopaque materials. Similarmarkers may also be applied to the waist section. The marker materialmay also be selected to enhance visibility under ultrasound imaging,magnetic resonance imaging, or other suitable imaging techniques.

FIGS. 20 and 21 illustrate mandrels or dies useful for forming andtraining/heat setting the shunt rivets. As shown in FIG. 20, a two partmandrel comprises a distal mandrel portion 63 and a proximal mandrelportion 64. Each mandrel is shaped to correspond to the desired finalshape of the shunt rivet and its clinch members. The mandrel portionsare inserted into the tube, after it has been cut, so as to deform thedevice. Where the device is formed from a pseudoelastic material thatmust be heat set or trained, the mandrels are dimensioned to deform thedevice to its desired open configuration. Where the device is formed ofspring steel or the like, the mandrel is dimensioned to bend the clinchmembers beyond the desired final configuration. Thus, the mandrel ofFIG. 20 and the mandrel of FIG. 21, though shaped differently, may beused to form quite similar shapes for devices made of nitinol and springsteel. The mandrel shapes may be modified as desired to achieve variousclinch member shapes, such as the asymmetrical shapes shown in FIGS. 12and 13.

The devices described above may be provided with coatings or additionalstructures which serve as matrices for various therapeutic compounds.Drug eluting coatings, additional drug eluting strut members, drugeluting membranes surrounding the central section or drug eluting massesfilling the cells of the device may be added to the devices. For theaorto-caval application and the arterio-venous application, therapeuticagents such as heparin and other anti-coagulants and paclitaxol,rapamycin (Sirolumis™), everolimus and other anti-stenotic compounds canbe applied to the stent in polymer matrices which permit elution ofthese drugs over a period of time ranging from several hours to severalmonths after implantation. Polymers such as polyurethane can be used asthe matrix.

While the preferred embodiments of the devices and methods have beendescribed in reference to the environment in which they were developed,they are merely illustrative of the principles of the inventions. Otherembodiments and configurations may be devised without departing from thespirit of the inventions and the scope of the appended claims.

1. A method of forming a medical device comprising: forming a generallytubular structure having a central section with a first diameter, aproximal clinch section defined by one or more clinch members, and adistal clinch section defined by one or more clinch members; trainingthe distal clinch members to be resiliently biased to bend radiallyoutwardly from the central section; training the proximal clinch membersto be resiliently biased to bend radially outwardly from the centralsection; expanding the central section through plastic deformation tosecond diameter.
 2. The method of claim 1 further comprising the stepsof: after training the proximal and distal clinch members, resilientlycompressing the tubular structure to maintain a generally tubular shapeand restraining the compressed tubular structure; releasing the tubularstructure to permit resilient expansion of the distal clinch members;thereafter performing the step of expanding the central section throughplastic deformation to a second diameter.
 3. The method of claim 1further comprising the steps of: after training the proximal and distalclinch members, resiliently compressing the tubular structure tomaintain a generally tubular shape and restraining the compressedtubular structure; introducing the compressed structure percutaneouslyto a site within the body; inserting the structure through apposingapertures in the aorta wall and vena cava wall of a patient such thatthe distal clinch members protrude into the vena cava of the patient andthe central section is disposed within the apertures; and thereafterreleasing at least a portion of the tubular structure to permitresilient expansion of the distal clinch members; and thereafterperforming the step of expanding the central section through plasticdeformation to a second diameter.
 4. The method of claim 1 furthercomprising the steps of: after training the proximal and distal clinchmembers, resiliently compressing the tubular structure to maintain agenerally tubular shape and restraining the compressed tubularstructure; and thereafter inserting the structure through apposingapertures in the aorta wall and vena cava wall of a patient such thatthe distal clinch members protrude extend into the vena cava of thepatient and the central section is disposed within the apertures; andthereafter releasing the distal clinch members to permit resilientexpansion of the distal clinch members; and thereafter performing thestep of expanding the central section through plastic deformation tosecond diameter; and releasing the proximal clinch members to permitresilient expansion of the proximal clinch members.
 5. The method ofclaim 1 further comprising: forming the tubular structure from apseudoelastic material, said pseudoelastic material being pseudoelasticat body temperature.
 6. The method of claim 1 further comprising:forming the tubular structure from a resilient material.
 7. A method oftreating COPD comprising: providing a device having a central tubularsection with a first diameter, a proximal clinch section defined by oneor more clinch members, and a distal clinch section defined by one ormore clinch members; said distal clinch members being resiliently orpseudoelastically biased to bend radially outwardly from the centralsection; said proximal clinch members being resiliently orpseudoelastically biased to bend radially outwardly from the centralsection; making a first perforation or aperture or hole or incisionthrough the aorta of the patient and a second incision in the vena cavaof the patient, said first and second incisions being in apposition soas to permit insertion of the device through both incisions; compressingthe device into a generally tubular configuration and inserting thedevice into the distal end of a catheter; percutaneously inserting thedevice into the perforation or aperture or hole or incision so that thedistal clinch members extend into the vena cava and the proximal clinchmembers extend into the aorta; releasing the distal clinch members fromthe catheter to allow the distal clinch members to resiliently orpseudoelastically bend outwardly to form a distal clinch operable toimpinge on the vena cava wall proximate the incision; releasing theproximal clinch members from the catheter to allow the proximal clinchmembers to resiliently or pseudoelastically bend outwardly to form aproximal clinch operable to impinge on the aorta wall proximate theincision; and expanding the central section through plastic deformationto a second diameter.